Originally Posted by BluPhant
...1. Get your Wii's mac address:The MAC address of the Wii can be found by:
From the Wii Channel menu, select "Wii Settings" (the round button on the bottom-left of the screen with "Wii"
on it)
Select "Internet," then "Console Settings."
The MAC address of the Wii console is displayed on the first line.
2. Format your SD card. Fat32
Panasonic SDFormat preferred. Dont skip this step.
3. Download the HackMii installer
You can use the mac address to build a custom hackmii installer at LetterBomb
MAKE SURE YOU SELECT YOUR REGION up top
If you get the captcha wrong, it will RESET your region. This happened to me. If you do, the installer, well,
in my case hung the wii. Had to hard boot it.
4. Copy downloaded files to root directory of SD card. I used windows xp.
5. Put card in wii and start it.
6. Hit the envelope in the lower right hand corner
If you dont see the red message with the bomb, hit the - or + buttons to choose a different date.
7. Click on the big red envelope with the bomb.
The hackmii installer launches. (note if it hangs, you might not have done step 2, or you might have chosen
the incorrect region)...
-Blu

After re-downloading it again, it now seems to work. Does this procedure really rely on the Wifi's MAC address? The more I think about it, the more it make sense to search the download files for the MAC address.